PROJECT SUMMARY/ABSTRACT There remains a wide gap in the US between the care children should receive and the care they do receive. The federal Pediatric Quality Measures Program (PQMP) was created to develop quality measures for diverse settings and purposes. Through the PQMP, we received funding to establish the Center of Excellence for Quality Measurement (CEPQM) to develop and test child quality measures. Working with multiple states and stakeholders, we developed measures in areas of critical importance to payers, providers, and families. For the PQMP's current dissemination and implementation stage, our specific aims are to convene a multidisciplinary partnership team and collaborate with Massachusetts (MA) and New York (NY) to: (A) field test two measure sets to ensure validity, feasibility, and usability for states, health plans, and hospitals, and further develop strategies to streamline data collection and measure reporting; and (B) use performance data to define quality improvement (QI) goals, assess intervention effects, and drive state-level improvement. We have selected two of our measure sets: (1) pediatric 30-day readmissions, comprising two measures, All-Condition Readmissions and Lower Respiratory Infection Readmissions, and (2) family experience of pediatric inpatient care, comprising the 18 measures included in the Child Hospital Consumer Assessment of Healthcare Providers and Systems (Child HCAHPS) Survey. Both measure sets are harmonized with the corresponding adult measures used by the Centers for Medicare and Medicaid Services (CMS), other payers, and many US hospitals. Both readmission measures and Child HCAHPS have been endorsed by the National Quality Forum. In addition, All-Condition Readmissions and Child HCAHPS were prioritized by the Measure Applications Partnership in 2015 and 2014, respectively, for inclusion in the CMS Child Core Set. Our multidisciplinary partnership includes academic researchers; representatives from MA and NY health departments, External Quality Review Organizations, health plans, and hospitals; and QI experts from the Institute for Healthcare Improvement and National Improvement Partnership Network. We will also enhance our measures; for instance, we will test improving the readmissions case-mix model through including electronic health record data, and administering Child HCAHPS on day of discharge to increase participation. Our QI strategies will be grounded in the theory and practice of implementation science and will include analysis of contextual factors that affect current performance, identification of key drivers of improvement, development of intermediate process measures, and local tests of change. Reducing preventable readmissions and improving family experience of inpatient care are among the highest priorities for our health system. Through this project, we aim not only to advance knowledge about how to apply measures effectively, but also to produce strategies and tools that can be applied to implementation and care improvement in many measure domains and across the entire country.